I think there is an evil spirit in my house.... but im not sure if it is something else. Help?

You experienced something called sleep paralysis while lying in bed. During sleep paralysis, it feels as if something is sitting against your chest and you can't move, and you won't be able to cry out at all. You'll also hear and see things as if your dreaming even when your eyes are open. You usually fall asleep afterwards. If you'd like to know more, please read the wiki article.